package strings;

import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class JGrep {
	public static void main(String[] args) throws Exception {
		if (args.length < 2) {
			System.out.println("Usage: java JGrep file regex");
			System.exit(0);
		}
		Pattern p = Pattern.compile(args[1]);
		int index = 0;
		Matcher m = p.matcher("");
		for (String line : Files.readAllLines(Paths.get(args[0]))) {
			m.reset(line);
			while (m.find())
				System.out.println(index++ + ": " + m.group() + ": " + m.start());
		}
	}
}
